Hemorrhagic disease of the newborn remains a significant problem in third world countries where prophylactic vitamin K administration is not in general use. All newborns are deficient in vitamin K as compared to adult levels. In addition, high incidence of PIVKA (Proteins Induced by Vitamin K Absence) proteins have been noted in otherwise healthy full-term newborns. The etiology of these PIVKA proteins is not clearly understood and is the focus of this study. Thirty healthy full-term newborns delivered by caesarean section will be studied. Umbilical cord blood samples (prior to the administration of vitamin K) will be compared to neonatal samples obtained at 3 days of age following the administration of vitamin K. Data has been collected and is being analyzed.